1. Field of the Invention
The present invention relates to a rotary compressor to compress a refrigerant, and refrigeration cycle equipment such as an air conditioner and refrigerator using the rotary compressor.
2. Description of the Related Art
Large capacity has been demanded in a rotary compressor, which contains a motor unit and a compression mechanism in a sealed case, transmits the rotational power of the motor to the compression mechanism through a rotary shaft and crankshafts eccentrically provided in the rotary shaft, and compresses a refrigerant in the compression mechanism.
For example, Jpn Pat. Appln. KOKAI Publication No. 08-144976 (patent document 1) discloses a rotary compressor comprising a 2-cylinder compression mechanism, which is formed to accord with the following equation, assuming the inside diameter of the cylinder to be φDa, the height of the cylinder to be H, and the eccentricity of the crankshaft to be E.H/(φDa•E)=0.07−0.13
However, in this configuration, optimum balance between mechanical loss and leakage/heat receiving loss does not meet a conventional design value (0.07−0.13), and highest efficiency is difficult in the compression mechanism.
Jpn Pat. Appln. KOKAI Publication No. 2006-37893 (patent document 2) proposes technology to solve the above problem and realize highest efficiency. This patent application discloses a 2-cylinder rotary compressor, in which the cylinder is formed to accord with the following equation, assuming the inside diameter of the cylinder to be φDa, the height of the cylinder to be H, and the eccentricity of the crankshaft to be E.0.05≦H/(φDa•E)<0.07
It is known particularly in a rotary compressor that a crankshaft, and the ratio of the crankshaft diameter φDb to the sliding length L of a roller fitted in the crankshaft (L/φDb) have a large influence on a sliding loss in a compression mechanism. However, the above patent document 2 mentions nothing about the ratio (L/φb).